1. Verification-driven design and programming of autonomous robots
- Author
-
Izzo, Paolo and Veres, Sandor M.
- Subjects
629.8 - Abstract
This thesis describes a new agent-based architecture called the Limited Instruction Set Agent (LISA). Agent-based systems are a popular approach to the implementation of autonomous behaviour, and they usually consist of a 'reasoning' module that commands lower level subsystems that in turn interact with the environment. When an autonomous system is placed in any environment, the correctness of the software must be guaranteed for safety. This is generally done with 'verification by model checking' which consists of creating a model, which represents the system and its interaction with the environment, and then proving specifications using the model. Most agent frameworks to date do not contemplate verification as a design feature and they generally share a few drawbacks: the generation of a model that can be verified by a model checking software is either done manually or by executing the agent code recursively and exploring every possible path to list the state space of the system. The LISA system is based on existing agent-based architectures and it is designed to be structurally simpler than its predecessors with the aim of facilitating the verification process. The agent program of LISA is enriched with structures that allow to model the probabilistic nature of environmental events, so that they can be taken into account in the verification process. The LISA program can be automatically translated to a verifiable probabilistic model suitable for verification with existing software tools such as PRISM. Furthermore, the system is structured to minimise the size of its probabilistic model, and ultimately offers a faster verification process. The thesis contains a number of theoretical contributions to the LISA programming system, including run-time verification for prediction of future outcomes of actions, and the new methods are illustrated on the programming and simulation with an example of autonomous surface vehicle for sea mine detection and disposal.
- Published
- 2016